OLED (organic light-emitting diode) has become a next generation of flat panel display technology after the LCD (liquid crystal display), due to characteristics such as all-solid state, self-luminous, high contrast, wide viewing angle etc.
The OLED includes a transparent anode, an organic light-emitting layer and a metal cathode. When appropriate voltages are respectively applied to the anode and the cathode, holes of the cathode and charges of the anode are combined in the organic light-emitting layer to generate light. Depending on the composition of the organic light-emitting layer, light of the three primary colors red, green and blue can be produced, thereby forming light of basic colors.